Analog raw SAR data reduction using dynamic range limiting: background and experimental results with the PHARUS system

Author(s):  
L. Bierens ◽  
M. Otten
Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1683
Author(s):  
Winai Jaikla ◽  
Fabian Khateb ◽  
Tomasz Kulej ◽  
Koson Pitaksuttayaprot

This paper proposes the simulated and experimental results of a universal filter using the voltage differencing differential difference amplifier (VDDDA). Unlike the previous complementary metal oxide semiconductor (CMOS) structures of VDDDA that is present in the literature, the present one is compact and simple, owing to the employment of the multiple-input metal oxide semiconductor (MOS) transistor technique. The presented filter employs two VDDDAs, one resistor and two grounded capacitors, and it offers low-pass: LP, band-pass: BP, band-reject: BR, high-pass: HP and all-pass: AP responses with a unity passband voltage gain. The proposed universal voltage mode filter has high input impedances and low output impedance. The natural frequency and bandwidth are orthogonally controlled by using separated transconductance without affecting the passband voltage gain. For a BP filter, the root mean square (RMS) of the equivalent output noise is 46 µV, and the third intermodulation distortion (IMD3) is −49.5 dB for an input signal with a peak-to peak of 600 mV, which results in a dynamic range (DR) of 73.2 dB. The filter was designed and simulated in the Cadence environment using a 0.18-µm CMOS process from Taiwan semiconductor manufacturing company (TSMC). In addition, the experimental results were obtained by using the available commercial components LM13700 and AD830. The simulation results are in agreement with the experimental one that confirmed the advantages of the filter.


1988 ◽  
Vol 110 (4) ◽  
pp. 450-455 ◽  
Author(s):  
A. Fourmaux ◽  
R. Gaillard ◽  
G. Losfeld ◽  
G. Meauze´

This paper presents the ONERA contribution in a joint experimental program on the aerodynamics of supersonic airfoil cascades. The first part deals with the specific ONERA way of running cascade tests: description of the test facility, the test model, the instrumentation, and data reduction. Then, after a brief theoretical analysis of the ARL 19 cascade, some experimental results are presented and discussed.


Author(s):  
XUEJUN LIAO ◽  
ZHENG BAO

A new scheme of radar target recognition based on parameterized high resolution range profiles (PHRRP) is presented in this paper. A novel criterion called generalized-weighted-normalized correlation (GWNC) is proposed for measuring the similarity between PHRRP's. By properly choosing the parameter of the mainlobe width in GWNC, aspect sensitivity of PHRRP's can be reduced without sacrificing their discriminative power. Performance of the scheme is evaluated using a dataset of three scaled aircraft models. The experimental results show that by using GWNC, only a small number of most dominant scatterers can achieve the same recognition rates as HRRP's, thus leading to a significant data reduction for the recognition system.


Robotica ◽  
2002 ◽  
Vol 20 (4) ◽  
pp. 417-427 ◽  
Author(s):  
H.A. Talebi ◽  
K. Khorasani ◽  
R. V. Patel

In this paper, the problem of tip position tracking control of a flexible-link manipulator is considered. Two neural network schemes are presented. In the first scheme, the controller is composed of a stabilizing joint PD controller and a neural network tracking controller. The objective is to simultaneously achieve hub-position tracking and control of the elastic deflections at the tip. In the second scheme, tracking control of a point along the arm is considered to avoid difficulties associated with the output feedback control of a non-minimum phase flexible manipulator. A separate neural network is employed for determining an appropriate output to be used for feedback. The controller is also composed of a neural network tracking controller and a stabilizing joint PD controller. Experimental results on a single-link flexible manipulator show that the proposed networks result in significant improvements in the system response with an increase in controller dynamic range despite changes in the desired trajectory.


2004 ◽  
Vol 261-263 ◽  
pp. 1575-1580
Author(s):  
Tae Sam Kang ◽  
Sang Kyung Sung ◽  
Chul Hyun ◽  
Byeung Leul Lee ◽  
Jang Gyu Lee ◽  
...  

In this paper, presented are design, analysis, and experimental result of a tunable surface micromachined resonant accelerometer, ACRC-RXL. Also fabrication process of mechanical structure is illustrated. We used 40[μm] thick epitaxially grown polysilicon as structural layer and sealing area. With the exception of the CMP process, for smoothing the bonding area, the fabrication processes are simple as the conventional surface micromachining process. Experimental results show that the developed accelerometer has a performance of bias stability about 0.5mg and dynamic range over 10g.


2021 ◽  
Vol 263 (5) ◽  
pp. 1095-1106
Author(s):  
Tsubasa Yoshizawa ◽  
Atsushi Yoshida ◽  
Kenta Iwai ◽  
Takanobu Nishiura

Recent studies have been proposed to extract speech from the captured video of objects vibrating by sound waves. Among them, from the viewpoint of equipment cost, the method of extracting speech from the video captured by rolling-shutter cameras, which are widely used in consumer digital single-lens reflex cameras, has been attracting attention. The conventional method with the rolling-shutter video uses a grayscale video for processing based on phase images. However, a grayscale video has a smaller dynamic range than an RGB video, and thus the speech extraction accuracy of the conventional method degrades. Therefore, this paper proposes a speech extraction method based on RGB-intensity gradients on an RGB video to improve speech extraction accuracy. The proposed method extracts the speech by calculating the similarity of R, G, and B intensity gradients, and using these three intensity gradients expands the dynamic range. The experimental results on the quality and intelligibility of the extracted speech show our proposed method outperforms the conventional method.


2004 ◽  
Vol 834 ◽  
Author(s):  
H. Dötsch ◽  
C. Holthaus ◽  
A. Trifonov ◽  
M. Klank ◽  
O. Hagedorn ◽  
...  

ABSTRACTRare-earth iron garnet films of high quality can be grown by liquid phase epitaxy on paramagnetic substrates of gadolinium galliumgarnet. Such films are currently used for imaging of the spatial distribution of magnetic fields. This application is based on the Faraday rotation which can strongly be enhanced by bismuth incorporation.The physical properties of the films can be controlled by the chemical composition, the growth conditions and the crystallographic orientation. The sensor properties like sensitivity, dynamic range, signal linearity and unambiguity must be optimized according to the application desired. These properties, however, are not independent of each other. In addition, they strongly depend on the optical wavelength. Thus, it is necessary to find compromises.The influence of Faraday rotation, Faraday ellipticity, optical absorption, magnetic anisotropies and film thickness on the performance of a magnetooptical indicator film is investigated. Based on the swing of the photoresponse, a new optimization process is introduced. The process is experimentally verified and application examples are demonstrated.Furthermore, two methods are presented to enhance the sensitivity of magnetooptical sensors. Using specific crystallographic orientations, an easy plane of magnetization can be induced which is inclined with respect to the film plane. If the magnetization lies in this plane a very high sensitivity is achieved. The dependence of the geometrical orientation of the easy plane on the growth direction is calculated and the sensitivity and dynamic range are derived. Experimental results of a [112] oriented garnet film are in good agreement with calculations.Garnet films which are magnetized along the film normal due to a strong induced uniaxial anisotropy support magnetic domains. If the collapse field perpendicular to the film plane is small, such films can be used as very sensitive indicator films. Such films are easier to prepare than sensitive in-plane films. However, the spatial resolution is limited by the size of the domains. This disadvantage can be avoided by applying a bias field in the film plane. Directly at the in-plane collapse field the sensor film is in-plane magnetized yielding high spatial resolution at still high sensitivity. The variation of magnetooptical images with in-plane induction is demonstrated. Experimental results are in agreement with calculations.


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